Current post harvest disinfection treatments against insects on vegetables, grain, fruits, nursery stocks and other agricultural commodities rely heavily on chemical fumigation with chemicals such as e.g., methyl bromide and/or hydrogen cyanide. Indeed, eight percent of the entire methyl bromide market is for post harvest disinfection of commodities such as grain, fruits, and vegetables. Unfortunately, however, there are a number of problems associated with the use of chemicals such as methyl bromide for the post harvest disinfection of agricultural products.
An exemplary problem associated with the use of chemical fumigants for post harvest disinfection is the problem of toxicity. Toxicity is an issue for consumers who must contend with the residual fumigants left on treated produce, and for the workers who endure exposure as they conduct the fumigation. Methyl bromide is extremely toxic. Indeed, according to the U.S. Environmental Protection Agency, methyl bromide is a Class I Acute Toxin. Known effects of exposure include brain damage, harm to the nervous system, lungs, kidneys and liver and sometimes even death.
In addition to the toxic consequences associated with chemical fumigation of agricultural products, chemicals e.g., methyl bromide, also have negative impacts on the environment. For example, methyl bromide is a Class I Ozone Depleter, and its use is responsible for at least 5 to 10 percent of worldwide ozone depletion. Fortunately for the environment, but unfortunately for industries dependent on its use, production of methyl bromide will soon be phased out under the Clean Air Act and Montreal Protocol. Thus, alternatives to methyl bromide are needed more than ever before.
Chemical fumigation is not compatible with organic products, which are gaining popularity in both the United States and abroad. In addition, the use of chemical fumigants such as methyl bromide or hydrogen cyanide can be expensive, and can cause injury to the produce undergoing fumigation, thereby resulting in unsalable products.
Furthermore, the use of fumigation greatly hinders the export of U.S. lettuce and other commodities to some countries e.g., Japan which have stringent phytosanitary requirements. Indeed, contaminated shipments are regularly rejected at the port of entry. Thus, fumigation issues are of interest to the export industry since eliminating fumigation has the potential greatly increase export of US lettuce and other fresh commodities to overseas markets.
Clearly then, what is needed in the art are cost effective, safe, convenient, and reliable methods for the killing of agricultural pests that do not damage the quality of the agricultural product undergoing treatment, and which also do not introduce toxic pesticides or other chemical residues. Fortunately, the invention disclosed herein addresses these and other needs.